The present invention relates to a poppet valve device, and especially to a poppet valve device which is rotatable around its axis.
If a poppet valve of a valve operating mechanism in an internal combustion engine is rotated around its axis, it is known to solve most of valve troubles such as burning damage owing to local overheating in a valve head, local wear in a valve face and a valve stem, sticking in the valve, and adhesion of combustion products to the valve face. A valve rotator is conventionally used to rotate a valve around its axis, as disclosed in Japanese Utility Model Laid-Open Pub. No.2-107706.
However, such a valve rotator requires high accuracy of each part, complicate structure and a number of parts, thereby increasing costs. It needs relatively high weight, thereby increasing inertia mass of the valve operating mechanism, so that it is inconvenient for a high speed engine.